Conveyor system

ABSTRACT

A storage and retrieval system for goods has two power operated conveyors movable in separate endless loops past two (or more) spaced apart picking stations, each picking station common to both conveyors. Each conveyor has bins with compartments in which goods are stored. Although the bins on each conveyor remain in the same sequence, the bins are movable relative to each other on the conveyor to define &#39;&#39;&#39;&#39;buffer&#39;&#39;&#39;&#39; zones which permit simultaneous picking by two spaced apart pickers. The control system for the conveyors includes a reader which receives digital data concerning a group of orders to be picked from a stack of cards, each card giving the identity, quantity, and distribution of one of the articles to be picked. The two conveyors are automatically stopped alternately with the bins containing ordered goods at the picking stations, and the operator at each picking station picks goods from the bins in accordance with a read-out unit which displays the card data. A plurality of packing lanes originate at each picking station and terminate at a plurality of packing stations. Each picker distributes goods to the separate packing lanes in accordance with the read-out unit at the picking station.

United States Patent Traube 1451 June6, 1972 [54] CONVEYOR SYSTEM RobertJ. Traube, San Mateo, Calif.

[73] Assignee: FMC Corporation, San Jose, Calif.

[22] Filed: Aug. 21, 1968 [211 App]. No.: 754,443

[ 72] Inventor:

Primary ExaminerEdward A. Sroka Att0rneyF. W. Anderson and C. E. TrippABSTRACT A storage and retrieval system for goods has two power operatedconveyors movable in separate endless loops past two (or more) spacedapart picking stations, each picking station common to both conveyors.Each conveyor has bins with compartments in which goods are stored.Although the bins on each conveyor remain in the same sequence, the binsare movable relative to each other on the conveyor to define buffer"zones which permit simultaneous picking by two spaced apart pickers. Thecontrol system for the conveyors includes a reader which receivesdigital data concerning a group of orders to be picked from a stack ofcards, each card giving the identity, quantity, and distribution of oneof the articles to be picked. The two conveyors are automaticallystopped alternately with the bins containing ordered goods at thepicking stations, and the operator at each picking station picks goodsfrom the bins in accordance with a read-out unit which displays the carddata. A plurality of packing lanes originate at each picking station andterminate at a plurality of packing stations. Each picker distributesgoods to the separate packing lanes in accordance with the read-out unitat the picking station.

5 Claims, 18 Drawing Figures PATENTEDJUH 6 1912 SHEET 01 0F 1 EN TOR.ROBERT J. TRAUBE ATTORNEYS PATENTEDJUH 6 I972 SHEET [12 [1F 11 o. NN Gr"NESTOR ROBERT J. TRAUBE 3422M G 6? 7 AT TORNE YS PATENTEDJUH s 1972SHEET 03 UP 11 IJ'VENTOR. ROBERT J. TRAUBE J 61/.

AT TORNEYS PATENTED 5 197? SHEU 0% OF 11 IN\ ENTOR. ROBERT J. TRAUBEATTORNEYS PATENTED 51973 3. 667, 588

SHEET 08 [1F 11 m Hf; (NC) (No) T Qi A X LS\ KY T CARD COLUMN COUNTERTENS UNITS 354 f A Y A 98765432, iodaflnelm432 5 1.120 U; H: 2.50 252 VIE ma 252 7 n2 i (no) r\ r\+ L H zI/ nabl"l2.b 254 CARD K 1 a A READERKX A mm 1 w \17 8 6 4 2 0 208 254 HEADER 9 n 4 "LL54 n5 CARD A A 20?. X,L J I A F F l A p A j 22a ARTICLE 552. r18 \84 CARD f r\ L BINARY CODE;EE- 2 DECIMAL [E 80 2 l'l'ao. 11% CONVERSION L r\ x J E ITIVENTOR.ROBERT J. TRAUBE ATTORNE YS PATENTED 6 I972 3,667. 588

SHEET 08 HF 11 zs ab fL 2.8213 ,Z'ZOb COUNTER 282a EVEN 2700. 350COUNTER 35:2- r ODD 22 Z! ZQZb Z84b 2840. 336 T 2. I Tub 293338 gi 19g b2554b 1 %2240. ay 4 RELAY 4 RELAY men 36 CIRCUIT CIRCUIT J ODD EVEN J 2A 4b 2905 290d 292a336, 29% IDENTlTY 2114 A 2:212. CIRCUIT A EVEN 2740.x 27Gb IDENTITY JERS INVENTOR. 1 ROBERT J. TRAUBE BIN STOP Z'Z6a ODDATTORNEYS CONVEYOR SYSTEM BACKGROUND OF THE INVENTION The presentinvention relates to a storage and retrieval system for goods stored inand taken from, for example, a warehouse.

In some warehouse systems, goods are stored in stationary bins, andorders are filled by pickers who travel throughout the warehouse fillingindividual orders. The articles are placed in a cart or other vehicle bythe picker, and the picker pushes or rides the vehicle throughout thewarehouse in filling the order. When the order is completed, the goodsare taken to a packing station for shipment to the customer. Orderfilling by this method requires an excessive amount of travel by thepicker and consumes a large amount of time for each order. The largenumber of papers or documents (one for each order) handled by the pickerslows the order filling and leads to errors and lost orders.

Other warehouse systems, although more mechanized, are subject to someof the same disadvantages as the less mechanized systems. For example,in many systems the individual carts with which the orders are pickedare replaced, or supplemented, by mechanized conveyors. In thesesystems, orders are picked from stationary or dead storage bins and areplaced on the conveyor for transport to a sorting station. At thesorting station, a sorter places the goods for each customer in anindividual container which, when all the goods for the order have beenreceived, is sent to a packer for that particular order. Although orderscan be filled more quickly by this system than with less mechanizedsystems, it is necessary for a picker, sorter, and packer to handle eachorder, and to handle the papers for that order, before the order iswrapped for shipment.

SUMMARY OF THE INVENTION In the system of the present invention, only apicker and a packer handle each order, and neither need move about tocollect the articles of the order. Moreover, both handle a plurality oforders simultaneously to substantially reduce the amount of time eachspends on each order. A minimal amount of papers are handled in thesystem of the present invention while picking or packing the orders, andthus the order handling time and the delays caused by lost or misplacedorder sheets are reduced. In the preferred form of the invention, anendless conveyor has a plurality of coded containers, or bins, thereonwhich move past two spaced picking stations in a predetermined sequence.

A group of orders for articles to be shipped, for example, to a group ofstores, is placed on cards, each card indicating the quantity of asingle article which is to be shipped to each store in the group. Eachcard also indicates the total quantity of articles needed and thelocation of the stored articles on the conveyors. These cards may, forexample, be produced by a computer which divides the large number oforders (say, 300) received each day into small groups of orders of, forexample, six orders per group. The orders are grouped on a basis to suitthe convenience of the user of the system. For example, the orders canbe grouped in the required order of shipment, or according to the mode,or vehicle of shipment. Thus, out of say 300 orders, 50 groups of ordersare compiled by the computer. Two significant advantages, in addition tothe convenience of handling the orders in the sequence of shipment oraccording to vehicle or mode of shipment, accrue from batching theorders. First, a larger quantity of each article is usually picked,increasing the efficiency of the picker. Secondly, and more important, agreater proportion of bins will supply items to each picker on a singlerevolution of the conveyor than if a single order were picked, therebyminimizing conveyor travel per article picked.

The 50 groups of orders would be equally divided among the pickers. Withtwo pickers, half the orders would be picked at one picking station atapproximately the same time the other half are being picked at the otherpicking station. Thus,

the computer, in compiling, the 50 groups of orders, arranges 25 groupsof orders for picking at the first picking station and arranges theother 25 groups for picking at the other picking station. The twocategories of groups differ in the starting bin. The bins do not fillthe conveyors so there are buffer zones, or slack, which permitsrelative movement between bins. Therefore, no exact correlation isrequired between the groups of orders picked at one station and thegroup of orders picked at the other station. Thus, any group from thecategory arranged for picking at the first picking station can be pickedsimultaneously with any group from the category arranged for picking atthe other station.

The order cards for a group of orders from the category arranged forpicking at the first station is placed in a card reader at the firstpicking station where the information on each card is displayed, card bycard, on a read-out unit at that station to inform the picker whatarticles are to be picked. At about the same time, the order cards for agroup of orders from the category arranged for picking at the secondstation, is placed in a card reader at the other, or second, pickingstation where the information on each card is displayed, card by card,on a read-out unit at that station to inform the picker at that stationwhat articles are to be picked, the total quantity of each article, andthe distribution of the total quantity among the several orders.

The conveyor bins, which can be disengaged from the conveyor drivemechanism, do not fill up the conveyor. Although the bins always remainin the same sequence around the endless loop of each conveyor, the binsof a single conveyor can be moved with respect to adjacent bins becauseof intentionally provided slack on the conveyor to form the buffer"between pickers. When article card information is displayed on theread-out at each station, the bin containing that article is stopped bycontrol mechanisms so as to permit the operator to pick the totalquantity of that particular article needed to fill the six orders in theparticular group of orders currently in the card reader. The drivemechanism, however, runs continuously, and although a bin of a conveyoris stopped at one picking station another bin of the conveyor maysimultaneously be approaching the other picking station.

Six packing conveyors, one for each store order in the group, originateat each picking station and terminate, respectively, at six packingstations. As each picker takes the articles from the conveyor bin, thearticles are distributed, as indicated by the read-out unit, among thedifferent packing conveyorswhich carry them to the respective packingstations. Alternatively, in lieu of the six conveyors, six tote-bins areprovided to receive articles for the six orders of the group beingpicked. The articles are deposited in the tote-bins by the picker. Atthe conclusion of the complete picking cycle for the group of orderspicked, the tote-bins are transported to the packing station on thepacking conveyor.

After an article is picked and distributed among the small orders by apicker, he pushes a button which will erase from the read-out unit datafrom the card for that article and cause the data from the card for thenext article to be displayed on the read-out unit. Actuation of thebutton also releases the storage bin containing the article just pickedto clear the picking station for the storage bin containing the nextarticle required from that conveyor.

After each order is completed, a packer, who checks ofi the items asthey reach the packing station, packs the order for shipment to thecustomer.

It is therefore one object of the present invention to provide a storageand retrieval system in which a picker can pick articles withouttransportation delay between articles. It is another object of thepresent invention to coordinate the activities of two or more pickerswith respect to a storage conveyor.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of the system ofthe present invention;

FIG. 2 is a view in perspective of a portion of the system of FIG. 1;

FIG. 3 is a view taken on the line 3-3 of FIG. 2;

FIG. 4 is a view taken on the line 44 of FIG. 3;

FIG. 5 is a view in elevation, with parts broken away, of a motor forenergizing one of the conveyors;

FIG. 6 is a view taken on the line 6-6 of FIG. 3;

FIGS. 7 and 8 are views, respectively, of the header card and thearticle card utilized in the system of FIG. 1;

FIGS. 9, 10, 11, 12, 13 and 14 are schematic diagrams of the controlapparatus of the system of FIG. 1;

FIGS. 15 and 16 are views of the read-out units for a picking stationand six packing stations, respectively, for the system of FIG. 1;

FIG. 17 is a view in perspective of the code identifying indicia on thebin and the code detecting mechanism for a conveyor in a pickingstation; and

FIG. 18 is a schematic representation of a conveyor system with bufferzones as in the system of FIG. 1

DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in FIG. I, the storageand retrieval system disclosed herein has two live storage conveyors 10,12, each defining an endless loop. The inner conveyor moves in thedirection indicated by arrows A and the outer conveyor 12 moves in thedirection indicated by arrows B. Conveyor 10 lies in an endless pathwhich passes along one side of a first picking station 14 and along oneside of a second picking station 16. Conveyor l2 lies in an endless pathwhich passes along the other side of picking station 14 and the otherside of picking station 16. Picking station 14 is at one end of theloops (which are somewhat flattened and in a three sided array) definedby conveyors 10 and 12, and picking station 16 is at the opposite end ofthese loops. In other words, the distance along one side of each loopbetween the two picking stations is substantially equal to the distancealong the other side of each loop between the two picking stations. Itshould be understood that, if desired, additional picking stations canbe provided between the conveyors as indicated, for example, by dottedcircles at and 17. However, to simplify the disclosure, a system withthe two picking stations 14 and 16 only will be described.

As shown best in FIGS. 3, 4 and 5, each conveyor 10, 12 has two paralleltubular tracks 20, 22, each of which has. a slit 24 along the loweredge. The inner track of each conveyor loop receives a continuousendless chain 26, as shown best in FIG. 4, made up of links 27, 28connected together by universal couplings 30. Every other link (links27) has a horizontal guide roller 32 journaled therein and alternatelinks (links 28) have vertical support rollers 34 joumaled therein tofacilitate the movement of the chain through the tubular track. Anelectric motor 40 is mounted adjacent the track 20 of each conveyorloop. The motor 40 is connected by belt 42 to a gear reducer 44 whichhas an output shaft 46. A sprocket 48 mounted on the output shaftengages the chain 26 at an elongated opening 50 and dip 51 in thetubular track. The chain 26 is driven continuously during operation ofthe conveyor by motor 40.

A plurality of drive carriages 52 are connected to chain 26 at equallyspaced intervals and are continuously driven thereby around the loopdefined by the conveyor. Each carriage 52 has a pair of parallel spacedapart straps 54 which receive therebetween two connectors 56. Eachpivotal connector has a base 59, pivotally secured between straps 54.The base 59 has a head 61 pivotally received in a U-shaped link 63 whichis pivotally connected to arms 57. A driving dog 58 is pivotallyreceived between straps 54 and a spring 60 is connected between theupper end of dog 58 and a lug 62 extending between straps 54. Spring 60biases the driving dog clockwise (as viewed in FIG. 4) with the lowerend of the dog against a stop 64 which is connected across the loweredges of straps 54.

As shown best in FIG. 6, a plurality of bin carriages 66 are suspendedfrom the outer track 22 of each conveyor 10, 12. For each bin carriage,there is a group 68 of links received in tubular track 22. Each group 68comprises three links (two end vertical links 28 and a centralhorizontal link 27), which, as in chain 26, are connected together Byuniversal couplings 30. Each bin carriage has two parallel spaced apartstraps 70 which receive therebetween two upstanding arms 72 pivotallyconnected at their upper ends to the depending arms 57 of end links 28of link group 68. Pivotally suspended from the straps 70 is a bar 74which is secured to the upper end of bins, or containers 76. Each bin 76has horizontal shelves 78 (see FIG. 2) and vertical dividers 79 whichdivide the bin into compartments 80.

The forward arm 72 (relative to the direction of movement as indicatedby arrow C) of bin carriage 66 has a laterally extending rod 82 securedthereto which extends inwardly into the path of the lower end of theyieldable drive dogs 58 on the drive carriages, as shown in FIG. 4. Whenthe drive dog on a drive carriage engages rod 82 of the bin carriage,and the bin is unrestrained, the spring 60 will prevent the dog fromyielding and the drive carriage will drive the bin along the conveyorloop until the bin is restrained. When the bin is restrained, thedriving dog will yield and pass over rod 82, returning to its normalupright position after passing the rod. Subsequent drive dogs on thesubsequent drive carriages, which continuously move around the conveyorloop, will also trip over the lateral rod 82 as long as the bin isrestrained. When the bin is released from restraint, the drive dog onthe next drive carriage will advance the released bin carriage. Thus,the conveyors 10 and 12 have bins 76 which move continuously toward thenext picking station unless restrained. Since the bins do not occupy allthe space on the conveyor, slack, or buffer zones are left between thepickers which permits relative movement between the bins. Such a systemcan be depicted schematically, as shown in FIG. 18, by a conveyor withsteps at each picking station and a downward slope between pickingstations. The bins move freely under the force of gravity until they arerestrained. The total space on the conveyor unoccupied by bins betweentwo picking stations defines a buffer zone between the two pickingstations. This buffer zone, or slack, on the conveyor eliminates theneed for precise coordination between the picking instructions at thetwo picking stations.

There are six packing conveyors a, 90b, 90c, 90d, 90e and 90foriginating at each picking station 14, 16 and terminating respectively,at six packing stations 92a, 92b, 92c, 92d, 92c and 92f. Each packingconveyor has an endless driven belt 94a, 94b, 94c, 94d, 94e and 94f,respectively, which carries articles placed thereon at the pickingstation up to and against an end stop 96a, 96b, 96c, 96d, 96e and 96f,respectively, at each packing station. Each packing station has a shortroller conveyor 98 to hold a container 100 which is being packed witharticles transported to the packing station from the picking station.When an order received at a packing station is complete, container 100is sealed and pushed to a gravity roller conveyor 102 which carries thesealed containers to a shipping station 104 where they are removed forshipment.

Assume, by way of example, that there are a total of 199 numberedconveyor bins 76, odd numbered bins consecutively arrayed on conveyor 10and even numbered bins consecutively arrayed on conveyor 12. Each bin asan example may have 16 compartments in which articles are stored. By wayof example, assume that the warehouse in which the system of the presentinvention is installed receives on the average of 300 orders a day from300 different stores. Assume that each order calls for an average of 20diiferent articles in quantities ranging, in the typical case, from tiveto 25 The efiiciency of picking can be materially increased byincreasing the quantity of articles picked from a bin compartment at anyone time. To accomplish this, the orders for each day are not handledindividually, but, instead, are divided into groups, each groupcontaining, for example, six orders. The

orders are grouped on any basis the user of the system may desire. As aconsequence of the grouping, the total requirement on a single pickingsequence is increased for many articles. Of greater consequence is thefact that a greater proportion of the total available articles will berequired on a single picking sequence for a group of orders, and thenecessary transport, or bin movement, time is prorated over a greaternumber of articles during a picking sequence.

For each group of orders, a single header card 110 (FIG. 7) is prepared.Each card has rows and columns, and the order numbers (or, morespecifically, the numbers assigned to the stores who have sent in theorders) are punched into the card, as indicated at 1 l 1. Three adjacentcolumns will represent the three digits of one store number, and the rowin which a hole is punched will indicate the particular digit in eachrow corresponding to the digits in the store number. The six orders willbe sent, respectively, to the six packing stations of one of the pickingstations, as indicated in FIG. 7. The first column of each header cardhas a hole punched in row zero to indicate that the card is a headercard.

For each article required in a group of orders, an article card 112(FIG. 8) is prepared. Each article card, which has columns and rows likethe header card, is coded by punched holes, as at 1 14, to indicate, forthat article, the following data:

1. Bin number in which article stored,

2. Compartment number in bin in which article stored,

3. The total quantity of that article required for the six stores of thegroup,

The quantity of the article required for each store of the gmup,

5. Whether the bin is to be released after article picked (bin notreleased if next article in same bin),

6. The number of the bin from which the next article on the otherconveyor must be picked (to stop the desired bin on the other conveyorif it reaches the picking station as current article being picked). Ifthe next bin number is on the same conveyor, that bin number does notappear on the card since that bin cannot enter the picking station untilafter the current bin is released.

In addition, the article card 112 has a hole punched in row 1, column 1to distinguish the article card from the header card which has a holepunched in row 0, column 1. The article card has a hole punched in row0" of column 32 if the bin is to be released after the current articleis picked therefrom. If the next article is located in the same bin, andthe bin must therefore remain in the picking station, no hole is punchedin the 0 row ofcolumn 32.

The cards for each group (one header card and a card for each articlerequired in that group) are combined with the header card on top. Ingeneral, the article cards are arranged in numerical order of the binson the conveyors. Each article card for another article in the same binfollows in numerical sequence of the compartment numbers. Preferably thearticle cards alternate between the odd and even conveyors. In otherwords, each article card for an article not in the same bin should befor a bin and article on the opposite conveyor from the conveyor onwhich the previous article was carried. In any event, the article cardsfor even numbered bins (which are in numerical order on conveyor 12)must be in numerical order and the article cards for odd numbered bins(which are in numerical order on conveyor must be in numerical order. Inthe illustrative system disclosed, half the articles are stored in theeven bins and the other half in the odd numbered bins.

However, an even numbered card may be placed ahead of a slightly lowernumbered odd card and an odd numbered card may be placed ahead of aslightly lower numbered even card to permit a sequence of alternate oddand even cards.

The cards for each group of orders are arranged in a sequence designedto permit substantially simultaneous picking of one group of orders atone picking station while another group of orders is being picked at theother picking station. As shown in FIG. 1, one picking station is on theopposite side of the loop from the other picking station. Thus,

the group of cards for one picker is arranged so that the first articlespicked are situated in bin number 1 while the group of cards for theother picker is arranged so that the first articles picked are situatedin bin number 100, assuming a total of 199 bins. For each group oforders, both conveyors 10 and 12 will make a complete revolution duringthe picking cycle. Preferably, the orders are grouped, and the headerand article cards are prepared, by a computer.

A stack of punched cards for one group of orders is placed in a cardreader in picking station 14 by the picker at that station. A stack ofpunched cards for another group of orders is placed in an identical cardreader 152 in picking station 16 by the picker at that station. Sincethe control apparatus for controlling the conveyor in response to thecoded card data supplied to the reader is the same for each pickingstation, only the control mechanism for picking station 14 (shown inFIGS. 9 to 15 inclusive) will be described.

The card reader 150 (see FIG. 9) senses the columns of each cardreceived therein consecutively and impresses, for each column, a signalat one of the terminals 151 (one for each digit as indicated)corresponding to the digit row at which the column has a punched hole.This signal is transmitted by lines 154 and received at one of the 10inputs 156 of a binary coded decimal (BCD) conversion unit 158. Thedigital input, as, for example, the number 7, is instantly transmittedto binary output terminals 160 which are code equivalents of the fourdigits 8, 4, 2 and l, as indicated. Thus, to represent a digit 7 atoutput terminals 160, a signal is required on the outputs, the codeequivalent of which totals 7, or, the output terminals 4, 2 and 1.

Each time the card reader 150 steps from one column to the next, a pulseis transmitted by line 162 to input terminal 164 of counter 166. Thecounter, which has ten and unit output terminals 168, 170, respectively,produces simultaneously a signal on one terminal 168 and on one terminal170 for each column of the card, thereby producing a unique signal foreach column of the card corresponding to the particular column of thecard being read at that instant. There is an AND circuit 172 for eachcolumn used on any of the cards, only a few of which are shown forsimplification and clarity of the drawings. Each AND circuit 172 has twoinput terminals 1720, 172b, one (172a) of which is connected by line173a to one of the tens output terminals 168 of counter 164 and theother (172k) of which is connected by line 173b to one of the unitoutputs 170. A signal (that is, a plus voltage) is transmitted from thecounter to one AND circuit 17 2 at any instant corresponding to thecolumn of the card being read at that instant. AND circuits 172 forcolumns I, 2, 3, 4, 5, 7, 32, 33, 34 and 35 only are shown, the columnscorresponding to each being indicated in a circle adjacent each of theAND circuits.

A signal is impressed on the 0 output terminal 151 of card reader 150when reading a card if a hole is punched in row 0 of column I of thecard to indicate the card is a header card; a signal is impressed on the1 output terminal 151 of card reader 150 when a card is in the reader ifa hole is punched in row 1 of column 1 of the card to indicate the cardis an article card. Input terminals 176 and 178 of a flip-flop circuit184 are connected, respectively, by lines 180, 182 to the outputterminals 185a, 186a of AND circuits 185, 186. One input terminal 185b,186b of each circuit 185, 186 is connected by line 187 to outputterminal 208 of AND circuit 172 for column 1. The other input terminals185e, 1860 of AND circuits 185, 186 are connected, respectively, to the0 and 1 terminals 151 of the card reader 150.

There is located, at each of the packing stations 92a, 92b, 92c, 92d,92c and 92f a read-out unit 190a, 190b, 1900, 190d, 190e and l90f (FIG.16), each containing three read-out digit units 192 (FIG. 10) with tubescapable of displaying any of the digits 0 to 9 depending on the signaltransmitted to the four input terminals 194. The tube unit 192 convertsan 8, 4, 2, 1 input code signal to a corresponding digit and displaysthat digit. The unit 192 is reset by a positive signal received at theinput terminal 195 thereof. The digit unit may, for example,

be a Burroughs Corporation NIXIE Tube Driver with tube BIP-8804.

A set of four AND circuits 196 is provided for each digit unit 192, oneAND circuit 196 for each input terminal 194 of the digit unit 192. EachAND circuit 196 has an input terminal 198 connected by line 200 to theoutput terminal 202 of flipflop circuit 184. A positive voltage will beimpressed on input terminal 198 when the card reader is reading a headercard. Each AND circuit 196 has another input terminal 204 connected byline 206 to the output terminal 208 of one of the AND circuits 172. EachAND circuit 196 also has an input terminal 210 connected by line 212 toone of the output terminals 160 of the binary coded decimal conversionunit 158. Thus, a particular AND circuit 196 will transmit a signal fromthe output terminal 214 thereof by line 216 to input terminal 194 ofread-out digit unit 192 when a header card is in the reader, the readeris reading the particular card column which controls the particular ANDcircuit 172, and a positive voltage is being transmitted from theparticular output 160 of the binary coded decimal conversion unit towhich the particular AND circuit 196 is connected. Thus, when thisoccurs, a particular digit is transmitted to a particular digit read-outunit 192 corresponding to the digit hole punched in the column of thecard currently being read. The header card has six three digit numberspunched therein providing in numerical code the identity of the order(or, more specifically, the store from which the order was received)which is to be received at each of the six packing stations. As the cardreader scans the columns consecutively of the header card, the storeidentifying code numbers are inserted in the read-out units 190 at thepacking stations, as shown in FIG. 16.

A read-out unit 232 (FIG. 15) in each picking station has a three digitdisplay 234 indicating required bin number, a two digit display 236indicating compartment number in the bin for the article, and a threedigit display 238 indicating the total quantity of that particulararticle required. Six two digit displays 240a, 2401:, 240e, 240d, 240sand 240f indicate the number of that particular article needed for eachcustomer, or order, of the group of orders.

Each digit display unit 242 (FIG. 10), which is identical to digit unit192, will indicate one digit and will retain that digit until reset by asignal at reset terminal 243. Each digit unit has four input terminals244 corresponding, respectively, to digits 8, 4, 2, l in the binarydecimal code. Each of the input terminals is connected to the outputterminal 246 of one of the AND gates 220 in a set of four. There is aset of four AND gates 220 for each digit on read-out unit 232 (only oneset of which is shown for simplification and clarity of the circuit).Each AND gate 220 has an input terminal 222 connected to the outputterminal 208 of AND gate 172. Each AND gate 220 also has an inputterminal 224 connected by line 226 to output terminal 228 of flip-flopcircuit 184.

Terminal 228 has a positive voltage impressed thereon whenever apositive voltage is produced at input terminal 178 of flip-flop circuit184. This occurs when an article card 112 (FIG. 8) in the readerproduced a pulse at the 1 output terminal 151 of card reader 150 and apulse is produced at the output terminal 208 of AND circuit 172 forcolumn 1. These pulses are transmitted to the input terminal of ANDcircuit 186. A pulse then appears at output terminal 186:: of ANDcircuit 186 which is transmitted by line 182 to input terminal 178 offlip-flop circuit 184. A pulse at input terminal 178 produces a signalat output terminal 228 of flip-flop circuit 184 to indicate that anarticle card is being read in the reader. Conversely, the presence of aheader card 1 10 (FIG. 7) in the card reader 150 produces a pulse at thetemtinal which produces a pulse at input terminal 185c of AND circuit185. This pulse, coupled with a pulse at input terminal 185!) fromoutput terminal 208 of AND circuit 172, produces an output pulse atoutput terminal 185a. A pulse at terminal 185a is transmitted by line180 to input terminal 176 of flip-flop circuit 184. A pulse at inputterminal 176 of flip-flop circuit 184 produces an output signal atoutput terminal 202 to indicate the presence of a header card in thereader.

A third input tenninal 230 of each AND circuit 220 is connected by line212 to one of the output terminals of binary coded decimal conversionunit 158. Thus, when an article card is in the card reader, and aparticular column of that card is being read, the digit indicated by thepunched hole in that column will be displayed on a digit read-out unit242. As the card reader at each picking station scans an article card,all the data on that card, which includes bin number, compartmentnumber, total quantity required, and quantity required for each store ofthe group, is displayed on the read-out unit 232 at that pickingstation.

Column 2 of each article card (FIG. 8) has a hole punched in the zerorow thereof if the bin number (columns 3, 4 and 5) is odd; no hole ispunched in column 2 if the bin number is even. The signal indicating thepresence of an odd bin number is transmitted by line 250 (FIG. 9) toinput terminal 252 of the AND circuit 172 which is connected (by lines173a, 1731;) to the tens output terminal 0 of counter 166 and to theunit output terminal 2 of the counter 166. Thus, if the bin number isodd, a signal will be transmitted to the output terminal 208 of the 2AND gate 172 to energize relay KX. The relay KX is sealed in through itsown normally open contacts KX and through the normally closed contactsK2. In the drawings normally open contacts are indicated (N0) andnormally closed contacts are indicated (NC).

All odd numbered bins are on conveyor 10 and all even numbered bins areon conveyor 12. The three AND circuits 172 corresponding to the cardcolumns 3, 4 and 5 which give the bin number (that is, the three ANDcircuits 172 connected to the units and tens output terminals of thecounter 03, 04, 05) have their output terminals 208 connected by lines254 to the input terminals 256 of OR gate 258 (FIG. 10). Thus, a signalis impressed on output terminal 260 of OR gate 258 whenever the cardreader is scanning either columns 3, 4 or 5 of the article card.

It will be noted (FIG. 8) that the columns 33, 34 and 35 of the articlecard are provided to indicate the next bin number required on the otherconveyor. The cards of each group are preferably arranged so that unlesssuccessive articles are required from the same bin, the cards willspecify alternately articles from an odd numbered bin and articles froman even numbered bin. Therefore, when this can be accomplished, the binnumber in columns 33, 34 and 35 will be even if the bin number incolumns 3, 4 and 5 is odd. Similarly, the bin number in columns 33, 34and 35 will be odd if the bin number in columns 3, 4 and 5 is even. Ifconsecutive articles are both from even numbered bins, because the nextarticle required from an odd numbered bin is too far away on conveyor10, or are both from odd numbered bins because the next article requiredfrom an even numbered bin is too far away on conveyor 12, the entry incolumns 33, 34 and 35 is nevertheless for the next required bin on theconveyor other than the conveyor transporting the particular articleidentified by the card.

The three AND circuits 172 corresponding to columns 33, 34, 35 (FIG. 9)have their output terminals 208 connected by lines 262 to OR circuit 264(FIG. 10). Thus, a signal is impressed on output terminal 266 of OR gate264 whenever the card reader is scanning either columns 33, 34 or 35 ofthe article card.

As shown in FIG. 11, there is a counter 270a, a relay circuit 272a, anidentity circuit 274a, and a bin stop circuit 276a for conveyor 10.There are similar elements 270b, 272b, 2741: and 276b, respectively, forconveyor 12. Because the elements for one conveyor are identical to thecorresponding elements of the other conveyor, only one set of theelements will be described.

A switching network, indicated generally at S (FIG. 10), serves toconnect the output terminal of one of the OR gates 260 or 266 to one ofthe sets of circuit elements provided for each conveyor and to connectthe output terminal of the other OR gate to the other set of circuitelements for the other conveyor. A line 280 connected to output terminal260 of OR gate 258 has two branches 280a and 280b. Branch 280a,

which contains normally open contacts of relay KX, is connected to theinput terminal 282a of counter 270a (FIG. 11), and to the inputterminals 284a of four AND gates 286a. Branch 280b, which containsnormally closed contacts of relay KX (FIG. 10), is connected to theinput terminal 282b of counter 270b (FIG. 11), and to the inputterminals 284b of four AND gates 286b. A line 288 (FIG. 10) connected tooutput terminal 266 of OR gate 264 has two branches 288a and 288b.Branch 228a, which contains normally closed contacts of relay KX, isconnected to the input terminal 282a of counter 270a (FIG. 11), and tothe input terminals 284a of AND gates 286a. Branch 288b, which containsnormally open contacts of relay KX (FIG. 10), is connected to the inputterminal 282b of counter 270b (FIG. 11), and to the input terminals 284bof AND gates 286k.

AND gates 286a have input terminals 290a which are connected to line 226to receive a positive signal when an article card is in the reader. ANDgates 286a also each have an input terminal 292a which is connected toone of the lines 212 to receive a digit in 8, 4, 2, 1 code from thebinary coded decimal conversion unit 158. If there is an odd number incolumns 3, 4 and of the card, indicating the desired part is in an oddnumbered bin, relay KX will be energized from the hole punched in column2 and the normally open KX contacts will be closed. When this occurs,the counter 270a will receive three impulses from branch line 280a, asthe reader scans columns 3, 4 and 5, and the relay circuit 272a willreceive, at the four input terminals 294a thereof, pulses (or no pulses)from the four AND gates 284a to present, in 8, 4, 2, 1 code, threeconsecutive digits corresponding to the three consecutive digits incolumns 3, 4 and 5 of the article card as they are read successively bythe card reader.

AND gates 28Gb have input terminals 290b which are connected to line 226to receive a positive signal when an article card is in the reader. ANDgates 286b also each have an input terminal 292b which is connected toone of the lines 212 to receive a digit in 8, 4, 2, 1 code from thebinary coded decimal conversion unit 158. When there is an odd number incolumns 3, 4 and 5 of the card, relay KX is energized and the normallyopen KX contacts are closed. Thus, since there is an odd number incolumns 3, 4 and 5, there will be an even number in columns 33, 34 and35. The digits in columns 33, 34 and 35 represent the next bin number onthe opposite conveyor, and each time the card reader reads one of thesedigits, an impulse is received by counter 270b through branch line 288k.At the same time, the relay circuit 272b will receive, at the four inputterminals 294 b thereof, pulses (or no pulses) from the four AND gates286b to present, in 8, 4, 2, 1 code, three consecutive digitscorresponding to the three consecutive digits in columns 33, 34 and 35as they are read successively by the card reader.

If an even numbered bin is called for in columns 3, 4 and 5 of thearticle card, column 2 will have no hole punched and relay KX will notbe energized. Thus, normally closed relay contacts KX will be closed andnormally open relay contacts KX will be open. Pulses will be transmittedfrom OR circuit 258 (FIG. through line 280 and branch line 280b tocounter 270b and to AND gates 286b (FIG. 11). Thus, the digits read bythe card reader in columns 3, 4 and 5 will be transmitted to relaycircuit 272b. The next bin number which appears in columns 33, 34 and 35will be odd. Three consecutive pulses will be transmitted from OR gate264 (FIG. 10) through line 288 and branch 288a to counter 270a and toAND gates 286a (FIG. 11). Thus, an odd number in columns 3, 4 and 5 orin columns 33, 34 and 35 will be will be transmitted to relay circuit272a to control the conveyor 10 which carries only the odd numberedbins. Similarly, an even number in columns 3, 4 and 5 or in columns 33,34 and 35 will be transmitted to relay circuit 27% to control theconveyor 12 which carries only the even numbered bins.

Since the elements 270a, 272a, 274a and 276a for the conveyor 10 of oddnumbered bins are identical to the elements 270b, 272b, 274b and 276bfor the conveyor 12 of even numbered bins, only the former elements willbe described. As shown in FIG. 12, the counter 270a has three outputterminals 300, 302 and 304. Lines 306, 308 and 310, each containingdiode 312, are connected, respectively, between the output terminals anda source of negative potential (represented by line 314). Line 306contains relay KR which is energized when the first, or hundreds, digitsof the odd bin number (either columns 3 or 33 of the article card) isread by the card reader. Line 308 contains relay KS which is energizedwhen the second, or tens, digit of the odd bin number (either columns 4or 34 of the article card) is read by the card reader. Line 310 containsrelay KT which is energized when the third, or unit, digit of the oddbin number (either column 5 or 35 of the article card) is read by thecard reader. Relays KR, KS and KT, when energized, are each sealed in bytheir own normally open relay contacts KR, KS and KT, which areconnected, respectively, between lines 300, 302, 304 and a source 318 ofpositive voltage through normally closed contacts 320 of push buttoncompletion switch PB.

The input terminals 294a of relay circuit 272a are connected by lines334 to the output terminals 336 of AND gates 286a (FIG. 11). Insiderelay circuit 272a, line 338 connects to the temiinal 294a whichrepresents 8 in the digit code; line 340 connects to terminal 294a whichrepresents 4 in the digit code; line 342 connects to terminal 294::which represents 2 in the digit code; and line 344 connects to terminal294a which represents 1 in the digit code. Each of these lines terminatein parallel branches containing normally open contacts of the relays KS,KT (lines 338, 340, 342) and KR, KS and KT (line 344). The contacts KR,KS and KT of line 344 connect to relays KA, KB and Kl, respectively. Thecontacts KS and KT of line 342 connect to relays KD and KH,respectively. The contacts KS, KT of line 340 connect to relays KC, KG,respectively. The contacts KS, KT of line 338 connect to relays KB, KF,respectively. Each of the relays KA, KE, KI, KD, KH, KC, KG, KB and KF,when energized, are sealed in through their own normally open contactsand through normally closed contacts of a relay K2. As indicated inblocks in FIG. 12, relays KA, KB and K1 are energized through line 344and contacts KR, KS, KT to indicate 100, 10 and l; relays KD and KH areenergized through line 342 and contacts KS and KT to indicate 20 and 2;relays KC and KG are energized through line 340 and contacts KS and KTto indicate 40 and 4; and relays KB and KP are energized through line338 and contacts KS and KT to indicate and 8.

The switch PB has normally open contacts 350 which, when closed,energize relay K2 connected in circuit with the contacts 350.Energization of relay K2 opens the normally closed contacts K2 which areconnected in series with each of the sealing contacts KA, KE, KI, KD,KI-I, KC, KG, KB and KF, in the relay circuit 272a. Thus, when contactsK2 in the relay circuit open, all the relays KA, KE, KI, KD, KI-I, KC,KG, KB and KF are released. Similarly, the relay KX (FIG. 9), which hassealing contacts connected in series with normally closed contacts ofrelay K2, is released. When contacts 350 of switch PB close, line 352 isconnected to positive voltage source 318. Line 352 terminates at resetterminal 354 of card column counter 166; at reset terminal 358 of cardreader at reset terminal 360 of counter 270a (FIG. 10); at resetterminal of digit unit 192 (FIG. 10); and at reset terminal 243 of digitunit 242. As contacts 350 of switch PB close, normally closed contacts320 open to deenergize relays KR, KS and KT.

When the first digit of a bin number (column 3 or column 33) is receivedat terminals 294a of relay circuit 272a (FIG. 12) from OR circuit 258 or264 (FIG. 10), a signal is simultaneously transmitted to counter 270a(FIG. 12) to energize relay KR, and only relay KR. Thus, the contacts KRof relay circuit 2723 are closed. It should be noted that since thehighest bin number is 199, the line 344 (which corresponds to l in the8, 4, 2, 1 code) is the only line with KR contacts. Thus, only relay KAis energized, if a pulse is received on line 344, and this relay issealed in through its own contacts. When the next digit of the binnumber (column 4 or column 34) is received at terminals 2940, a signalis simultaneously transmitted to counter 2700 to energize relays KS, andonly relays KS. If the digit requires a pulse on some of the 8, 4, 2, 1lines 338, 340, 342, 344, the relays KE, KD, KC and KB connected to thelines which receive a pulse, will be energized. When the last digit of abin number (column 5 or column 35) is received at terminals 294a, asignal is simultaneously transmitted to counter 270a to energize relayKT, and only relay KT. If the digit requires a pulse on some of thelines 338, 340, 342, 344, the relays Kl, KH, KG and KF connected tolines which receive a pulse, will be energized. The relays KA, KE, KI,KD, KH, KC, KG, KB, and KP, which, when energized, are sealed in throughtheir own contacts, indicate the bin number transmitted to the relaycircuit from the card reader. Thus, for example, if the bin number 177is transmitted to the relay circuit 272a, relay KA, KE, KI, KD, KH, KCAND KG (which represent, respectively, 100, l0, 1, 20, 2, 40, 4, asindicated in FIG. 12) will be energized and will be sealed in throughtheir own contacts. Relays KB and KP (which represent 80 and 8) will notbe energized.

Each bin 76 (FIG. 17) has code identifying indicia in the form of a codebar 370 depending therefrom. Each code bar has a series of actuatingrods 372 extending therethrough, the quantity and position of the rodsdetermined by the number of the bin. The rods are positioned to operatecertain switches of a set of nine switches, SA, SB, SC, SD, SE, SF, SG,SH and SI mounted on a panel 374, one set for each conveyor in eachpicking station. Each panel of switches, which comprises a codedetecting, or reading mechanism for each conveyor in a picking station,is mounted on a pedestal 375 (one for each conveyor) beneath theconveyor for which the panel is provided. Each panel of switches isoperated by the code bar of the bins of that conveyor. As indicated inFIG. 17, switch SA corresponds to 100, switch SB corresponds to 80,switch SC corresponds to 40, switch SD corresponds to 20, switch SEcorresponds to 10, switch SF corresponds to 8, switch SG corresponds to4, switch SH corresponds to 2, and switch S1 corresponds to l. The rods372 are arranged on code bar 370 to operate those switches, and onlythose switches, which add up to the bin number. Thus, bin number 177would have rods positioned to operate switches SA, SC, SD, SE, SG, SHand Sl. No rods would be provided to operate switches SB and SF.

The identity circuit 274a (FIG. 13) has contacts operated by the bincode switches at each picking station and by the relays in the relaycircuit 272a. If the bin which operates the switches at the pickingstation has the same number as the number placed in the relay circuit272a by the card reader, a circuit is made (FIG. 13) to connect thesolenoid SOLl (FIG. 14) across a source 380 of positive voltage and asource 382 of negative voltage. The solenoid, when energized, actuates astop 384 mounted on rail 22 in the picking station above pedestal 375and a short distance downstream from the code reading panel 374 on thepedestal. The stop 384, when actuated, moves into the path of the group68 of links which carry the bin, the code number of which is read at thepicking station, as shown in FIG. 6. Thus the stop 384 is controlled bythe card reader 150 through the network (shown in FIGS. 11, 12 and 13)by which the card reader 150 is connected to the stop 384 of circuits276a and 276k.

Normally closed switch contact K2, normally open contacts SA, SB, SC,SD, SE, SF, SG, SH, SI, KT, and normally closed switch contact K1 areconnected in series with relay TDl between positive and negative voltagelevels 380 and 382. Branch lines A31 and AB2, separated by a diode 386,are connected between switch contacts SA and SB; branch lines BCl andBC2, separated by a diode 386, are connected between switch contacts SBand SC; branch lines CD1 and CD2, separated by a diode 386, areconnected between switch contacts SC and SD; branch lines DB1 and DB2,separated by a diode 386, are connected between switch contacts SD andSE; branch lines EFl and EF2, separated by a diode 386, are connectedbetween switch contacts SE and SF; branch lines FGl and FG2, separatedby a diode 386, are connected between switch contacts SF and SG; branchlines GH] and 0H2, separated by a diode 386, are connected betweenswitch contacts SG and SH; branch lines All and HI2, separated by adiode 386, are connected between switch contacts SH and SI; branch lineslTl and 1T2, separated by a diode 386, are connected between contacts SIand KT. Sealing contacts TDI, which closes on energization of relay TDl,are connected around the series arrayed contacts SA, SB, SC, SD, SE, SF,SG, SH, SI, KT and K1.

Normally closed contacts KA are connected in line ABl; normally closedcontacts KB are connected in line BCl; normally closed contacts KC areconnected in line CD1; normally closed contacts KD are connected in lineDE]; normally closed contacts KE are connected in line EFI; normallyclosed contacts KF are connected in line FGl; normally closed contactsKG are connected in line GHl; normally closed contacts KH are connectedin line Hll; normally closed contacts KI are connected in line 1T1. Eachof the contacts KA, KB, KC, KD, KE, KF, KG, KH, KI are connected throughdiodes 388, respectively, and relay K1 to the source of negativevoltage.

Normally closed switch KA is connected from one side of switch contactsSA to the line AB2 on the other side thereof. Normally closed contactsKB are connected between lines A132 and BC2; normally closed contacts KCare connected between lines BC2 and CD2; normally closed contacts KD areconnected between lines CD2 and D52; normally closed contacts KE areconnected between lines DB2 and EF2; normally closed contacts KP areconnected between lines EF2 and FG2; normally closed contacts KG areconnected between lines FG2 and GI-l2; normally closed contacts KH areconnected between lines GH2 and H12; normally closed contacts KI areconnected between lines Hi2 and 1T2.

when the code number of the bin at the picking station is the same asthe code number imparted by the card reader to relay circuit 272a, thebin stop 384 will be extended to stop the bin in the picking station forpicking. For example, if the number sent to the relay circuit 272a bythe card reader is 177, relays KA, KE, Kl, KD, KH, KC and KG (FIG. 12)will be energized. Also, if bin number 17 7 approaches the pickingstation, the rods on the code bar thereof will close switches SA, SC,SD, SE, SG, SH and S1 in the picking station. Therefore, in the identitycircuit 2740 (FIG. 13), normally closed switch contacts KA, KC, KD, KE,KG, KH, and K1 will be open, while normally closed contacts KB and KPwill be closed. Similarly, the normally open contacts SA, SC, SD, SE,SG, SH and SI will be closed. A circuit will be completed throughcontacts SA, KB, SC, SD, SE, KF, SG, SH, SI, KT (which is closed whenthe third, or least significant, digit of a bin number is read by thecard reader) and normally closed contacts K1 to energize relay TDl.Energization of relay TD! closes the normally open contacts TDl of therelay (FIG. 14) to energize solenoid SOLl and extend step 384 into thepath of the bin number 177. If the code bar 370 of a different bin thanone called for by the card in the card reader closes all the switcheswhich would be closed by the code-bar on the desired bin, plus anadditional switch or switches, a circuit will be made through one of thelines AB], BCl, CD1, DEl, EFl, FGl, GHl, H11, or U1. This is because theswitch contacts in that line operated by relays not corresponding to anumber called for by the card in the reader (such as contacts KB) areclosed. If, therefore, the switch SB (which is a notch which wouldnt beclosed by the desired bin) is closed, relay K1 will be energized to opennormally closed contacts K1 and disable relay TDl.

Normally closed contacts K2 in relay circuit 274a will open when pushbutton completion switch contacts 350 are closed to energize relay K2.Opening of contacts K2 will release relay TDI, and deenergize SOLI toretract stop 384, thereby releasing the bin 177, if normally closedcontacts KY, which are connected across contacts K2, are open.

If the next article to be picked from an odd numbered conveyor islocated in a bin other than bin 177, contacts KY will be open so thatbin 177 will be released when contacts K2 open. If, on the other hand,the'next article from an odd numbered bin is to be picked from bin 177,the contacts KY will remain closed so that relay TD1 will remainenergized despite the opening of contacts K2 when the picking operatorpushes the completion button.

The operation of contacts KY is controlled from data on the articlecard. If the next article in an odd numbered bin is in a bin other thanbin 177, a hole is punched in the row of column 32 of the article card.An AND circuit 172 (FIG. 9) is provided for column 32, the circuithaving input terminals connected to the 3 terminal of the tens terminals168 and to the 2 terminals of the unit terminals 170 of card columncounter 166. Another terminal of AND circuit 172 is connected to the 0output terminal 151 of card reader 150. Thus, when the card reader isscanning column 32 and a hole ap pears in the zero row thereof, therelay KY, which is connected to the output terminal of circuit 172, willbe energized. Relay KY is sealed in through its own normally open switchcontacts and the parallel connected normally closed contacts K2 and thenormally closed limit switch contacts LS1. Limit switch LS1 is mountedin the picking station adjacent the stop 384 and is operated byretraction of the stop.

When the article card 1 12 indicates the bin is to be released, relay KYis picked up and sealed in, opening the contacts KY in circuit 274a(FIG. 13). When, on completion of picking, the operator pushescompletion button PB (which is mounted on pedestal 375) for the conveyorjust picked, to close contacts 350 thereof, relay K2 is energized toopen all normally closed contacts K2. Relay KY, however, is not releaseduntil after the bin stop has been released because the relay KY issealed in through normally closed contacts of limit switch LS1, whichcontacts remain closed until after the stop is retracted. Thus, contactsKY in circuit 274a remain open until after the bin is retracted so thatrelay TDI is released when relay K2 is energized by the operation ofcompletion button PB.

When card 112 indicates the bin is to be held for the next article to bepicked from the odd numbered bins, relay KY is not picked up becausethere is no hole in column 32 of card 112. Thus, contacts KY of circuit274a remain closed, and seal in relay TDl around the contacts K2 incircuit 274a. Thus, despite operation of push button PB by the operator,solenoid SOLl will remain energized to hold stop 384 extended.

In the operation of the conveyor system of the present invention, eachof the picking station operators is given one group of cards which theyplace simultaneously in their respective card readers 150 and 152. Eachpushes the completion button PB for both conveyors to reset all thecounters and prepare the system for the first card of the group. Thefirst card of each group is the header card, and, as the card readerscans the columns thereof, the numbers corresponding to the stores, theorders from which make up the particular group of cards in the reader,are read. The store numbers of each group are displayed on the read-outunits 192a, 192b, 1924:, 192d, 192e and 192]" at the packing stationswhich are supplied by the picking station at which the cards are read.

After the header card has been read, the operators push their respectivecompletion buttons to initiate reading of the first article card at eachstation. The bin number, compartment number, total number of articlerequired, and quantity of each article required for each order will bedisplayed on the read-out unit 232 at each picking station. At the sametime, the conveyor motors are started to start the bins of bothconveyors moving past the picking stations. The odd numbered bin firstcalled for at picking station 14 will be approximately at the oppositeend of the conveyor from the odd numbered bin first called for at thepicking station 16. Similarly, the even numbered bin first called for atstation 14 will be approximately at the opposite end of conveyor 12 fromthe even numbered bin first called for at picking station 16. In otherwords, for each conveyor, the bins at which the operators will pick fromsimultaneously will be spaced apart on the conveyor a distance equal tothe distance between picking stations.

When the firstbin called for at each picking station reaches thatstation, the bin is stopped by plunger 384. Assume, by way of example,that both stations require an odd numbered bin from conveyor 10 (say bin1 at station 14 and bin 99 at station 16). These bin numbers are placedon columns 3, 4 and 5 of the cards in the card reader, and thus data issupplied to the circuit elements 270a, 272a, 274a and 276a forcontrolling the conveyor 10 for odd numbered bins. At the same time, thenumber of the next bin required at each picking station (which is aneven numbered bin) appears in columns 33, 34 and 35 of the cards andthis data is, at this time, supplied to circuit elements 270b, 272b,274b and 276k for the conveyor 12 which carries the even numbered bin.The operation of these circuit elements will stop the next bin selectedon arrival at the picking station.

Thus, at each station, while the operator is picking articles from onebin (odd numbered), the next bin is moving toward the picking station,and is stopped on arrival at the picking station, so the operator,without delay, can switch his activities from one conveyor to the other.Thus the operator not only need not travel from one bin location to thenext in picking articles, but also he need not wait for the nextrequired bin to travel to him with the next article, since, with the useof two coordinated conveyors, bin travel on one conveyor occurs whilethe operator is picking from a bin on the other conveyor.

It will be noted that with releasable power drivers, each bin on eachconveyor can be stopped, or allowed to move, without regard to movementof bins at other parts of the conveyor except that the bins of eachconveyor must remain in the same sequence on the conveyor. Provision ofunoccupied space on each conveyor 10 and 12 gives elasticity to thesystem so bins of each conveyor between the respective picking stationsneed not be precisely coordinated. In other words, a fixed orpredetermined number of bins need not be present between the pickingstations.

As each picker picks the articles from a bin, the articles aredistributed by the picker, in accordance with the instructions on theread-out unit, to the packing conveyors which carry the distributedarticles to the packing stations. Alternatively, the articles may beplaced in tote-boxes by the picker, one totebox for each store. Thetote-boxes are then transported by any suitable means to a packingstation or stations. There may be a packer for each station, or a packerfor several stations, but, in either event, the packer is supplied withan invoice for each order to be packed. As the articles are received,they are checked off, and when the order is complete, the order ispacked and transmitted to a shipping zone.

As each picker finishes picking a particular article, the completionbutton PB for the conveyor on which the bin is mounted is pushed torelease the bin and, at the same time, to bring the next card into thecard reader. The next article card may indicate a requirement for anarticle in another compartment of the same bin, or for an article inanother bin on the other conveyor.

Although the best mode contemplated for carrying out the presentinvention has been herein shown and described, it will be apparent thatmodification and variation may be made without departing from what isregarded to be the subject matter of the invention as set forth in theappended claims.

Having completed a detailed description of the invention so that thoseskilled in the art could practice the same, I claim:

1. A storage and retrieval system comprising an endless conveyor havinga plurality of containers for the storage of material therein, saidcontainers mounted on the conveyor for movement past a plurality ofpicking stations in a predetermined sequence, said containers movable onthe conveyor relative to each other without disturbing the sequence ofthe containers to permit a container to be stopped at one pickingstation for removal of material therefrom without stopping containersmoving toward the other picking station, and means responsive to inputdata on material to be picked to control the movement of saidcontainers.

2. A storage and retrieval system comprising an endless conveyor havinga plurality of containers for the storage of articles therein, aplurality of picking stations adjacent the conveyor, each pickingstation having means therein to instruct the picker at that stationconcerning the articles to be picked from the containers, means to movesaid containers past the picking stations in a predetermined sequencewith each container movable on the conveyor relative to adjacentcontainers to permit banking of containers at a picking station to awaitpicking by the picker, and means operable in coordination with saidpicker instructing means to control the movement of the containers 3. Astorage and retrieval system comprising an endless conveyor having aplurality of containers for the storage of articles therein, a pluralityof picking stations adjacent the conveyor, each picking station having aread-out unit therein to instruct the picker at that station concerningthe articles to be picked from the containers, means to move saidcontainers past the picking stations in a predetermined sequence witheach container movable on the conveyor relative to adjacent containersto provide buffer zones on the conveyors, means to supply picking datato said read-out units coordinated in accordance with the containersapproaching each picking station, and means operable in coordinationwith said picking data to control the movement of containers relative tothe picking stations to stop selected containers at the stations forpicking.

4. A storage and retrieval system comprising an endless conveyor havinga plurality of coded containers for the storage of articles therein,said containers occupying less than all the space on said conveyor toleave slack thereon, a plurality of picking stations adjacent theconveyor, each picking station having a read-out unit therein toinstruct the picker at that station concerning the articles to be pickedfrom the containers,

means to move said containers past the picking stations in apredetermined sequence with each container movable on the conveyorrelative to adjacent containers to provide buffer zones on the conveyorwhereby a container can be stopped at one picking station withoutstopping all the other containers on the conveyor, a reader to supplypicking data to each of said read-out units coordinated in accordancewith the containers approaching each station, and a control systemincluding means to sense said codes on the containers, said controlsystem operable in response to said reader to stop selected containersto be picked at each picking station.

5. A storage and retrieval system comprising an endless con veyor havinga plurality of coded containers for the storage of articles therein,said containers movable with respect to each other on the conveyor andoccupying less than all the space on said conveyor to leave slackthereon, a plurality of picking stations adjacent the conveyor, eachpicking station having a read-out unit therein to instruct the picker atthat station concerning the articles to be picked from the containers,drive means on said conveyor to continuously advance each bin which isnot restrained past the picking stations in a predetermined sequence,stops at each picking station operable when actuated to stop the nextapproaching container and subsequent containers reaching the pickingstation while the stop is actuated, a reader to supply picking data tothe read-out units at each station, said data coordinated in accordancewith containers approaching the respective stations, and meansresponsive to operation of the reader and the codes on the containers toactuate the stops at each station when containers containing articles tobe picked reach the station.

1. A storage and retrieval system comprising an endless conveyor havinga plurality of containers for the storage of material therein, saidcontainers mounted on the conveyor for movement past a plurality ofpicking stations in a predetermined sequence, said containers movable onthe conveyor relative to each other without disturbing the sequence ofthe containers to permit a container to be stopped at one pickingstation for removal of material therefrom without stopping containersmoving toward the other picking station, and means responsive to inputdata on material to be picked to control the movement of saidcontainers.
 2. A storage and retrieval system comprising an endlessconveyor having a plurality of containers for the storage of articlestherein, a plurality of picking stations adjacent the conveyor, eachpicking station having means therein to instruct the picker at thatstation concerning the articles to be picked from the containers, meansto move said containers past the picking stations in a predeterminedsequence with each container movable on the conveyor relative toadjacent containers to permit banking of containers at a picking stationto await picking by the picker, and means operable in coordination withsaid picker instructing means to control the movement of the containers.3. A storage and retrieval system comprising an endless conveyor havinga plurality of containers for the storage of articles therein, aplurality of picking stations adjacent the conveyor, each pickingstation having a read-out unit therein to instruct the picker at thatstation concerning the articles to be picked from the containers, meansto move said containers past the picking stations in a predeterminedsequence with each container movable on the conveyor relative toadjacent containers to provide buffer zones on the conveyors, means tosupply picking data to said read-out units coordinated in accordancewith the containers approaching each picking station, and means operablein coordination with said picking data to control the movement ofcontainers relative to the picking stations to stop selected containersat the stations for picking.
 4. A storage and retrieval systemcomprising an endless conveyor having a plurality of coded containersfor the storage of articles therein, said containers occupying less thanall the space on said conveyor to leave slack thereon, a plurality ofpicking stations adjacent the conveyor, each picking station having aread-out unit therein to instruct the picker at that station concerningthe articles to be picked from the containers, means to move saidcontainers past the picking stations in a predetermined sequence witheach container movable on the conveyor relative to adjacent containersto provide buffer zones on the conveyor whereby a container can bestopped at one picking station without stopping all the other containerson the conveyor, a reader to supply picking data to each of saidread-out units coordinated in accordance with the containers approachingeach station, and a control system including means to sense said codeson the containers, said control system operable in response to saidreader to stop selected containers to be picked at each picking station.5. A storage and retrieval system comprising an endless conveyor havinga plurality of coded containers for the storage of articles therein,said containers movable with respect to each other on the conveyor andoccupying less than all the space on said conveyor to leave slackthereon, a plurality of picking stations adjacent the conveyor, eachpicking station having a read-out unit therein to instruct the picker atthat station concerning the articles to be picked from the containers,drive means on said conveyor to continuously advance each bin which isnot restrained past the picking stations in a predetermined sequence,stops at each picking station operable when actuated to stop the nextapproaching container and subsequent containers reaching the pickingstation while the stop is actuated, a reader to supply picking data tothe read-out units at each station, said data coordinated in accordancewith containers approaching the respective stations, and meansresponsive to operation of the reader and the codes on the containers toactuate the stops at each station when containers containing articles tobe picked reach the station.